Industrial chemicals are often stored in 55 gallon steel drums which are sealed entirely and accessible through a small bunghole in a lid at one end of the drum. The sides of the drum are usually corrugated in part, to strengthen the drum walls and provide rigidity. During use, a hose or pump is inserted into the drum through the bunghole, with the drum in a vertical position. Once the majority of the drum contents have been pumped out, the pump is removed and some of the remaining fluid in the drum can be poured out. Alternately, the drum can be fitted with a valve on the bunghole and then placed horizontally, relying primarily on the force of gravity for drainage.
Due to the configuration of the lip of the drum and the location of the bunghole, approximately 1.75 inches from the edge of the drum lid, it is nearly impossible to drain the drum entirely. When the drum is filled with acid or other hazardous liquids, careful draining of the drum contents is often skipped or at best performed hastily.
In fact, it is common to leave two or more liters of fluid inside the drum. The "empty" drum is, in many cases, taken to a land fill and crushed. When one multiplies this seemingly small volume by the huge numbers of drums which are dumped in U.S. land fills on a daily basis, one begins to realize the magnitude of the problem created by incomplete drainage. Proper draining of drums containing hazardous fluids, such as sulfuric acid, pesticides, and other chemicals before the drum arrives at a land fill would enormously decrease the amount of hazardous wastes that eventually end up loose in the environment.
Currently, people throughout the world are expressing a renewed interest in the issue of environmental safety. Corporations are even advertising how their policies reduce impact on the environment. Possible reasons why the 55 gallon drum has not been redesigned before to allow for more complete draining are that the size of the current drum is an industrial standard and that the current shape of the drum creates a very rigid container. Any redesign which changed the shape of the drum without reducing container strength would have widespread effects on how drums are shipped, stored and handled. An ideal solution would not change the outer drum dimensions, yet would provide for easy and near complete drum drainage.